Yes, under the circumstances, start from scratch is usually the best way to go. I had the same problem once on my 5 years old Dell Inspiron running Vista. I could not login at all, not even in Safe Mode. I ended up re-installing the Vista OS. Since she uses the computer for business, she should start learning the basic of maintaining a computer. It is a must, not a luxury. If she does not want her business interrupted by something like that. Reminds me of my old high school classmates. 50 somewhat years later, they all have college degrees. But when it comes to computer, they said " We didn't have computer class in college." And with all the higher education intelligence, they are afraid to learn. Meanwhile, I self-taught myself in computer and I have less "higher education" than most of them.